Key lock



Sept. 18, 1945. v J.- w. NlLEY 2,385,244

KEY LOCK Filed May 9, 1944 IN VEN TOR.

ATTORNEYS Patented Sept. 18, 1945 UNITED STATES PATENT OFFICE KEY LOCK John W. Wiley, New York, N. Y. Application May 9, 1944, Serial No. 534,715

4 Claims.

The invention relates to a key lock by means of which it is impossible to turn a key in a locked door from the outside by manipulation through the key hole. The key lock hangs upon the door knob of the door and a portion thereof engages the key so as to prevent rotation thereof. The key lock carries a strip or extension member which passes through the loop or eye of the key and thereby prevents rotation thereof by manipulation from the outside of the door in an attempt to remove the key from the lock.

It is an object of the invention to construct a key lock having an open entrance passage into an elongated loop which receives the shank of the door knob and a device which is unbalanced and consequently vertical movement of the key lock in order to release or insert the same within the eye of the key prevents inadvertent removal of the device through the open entrance passage.

Another object of the invention is to construct a key lock which is unbalanced in its construction by locating the stem which engages in the eye of the key along one edge of the key lock.

Other objects of the invention will be more apparent from the following description taken in connection with the accompanying drawing illustrating a preferred embodiment thereof in which,

Figure 1 is a side elevation of the key lock.

Figure 2 shows the key lock positioned upon a door knob shank and with the stem or strip engaging in the loop of a key.

Figure 3 is a partial view of a key with the stem therein.

The key lock includes a body I providing an elongated opening I I therein for receiving the shank S of a door knob. The opening I I is elongated in order to enable the key lock to be moved vertically on the door knob shank without requiring removal of the key lock therefrom. The body of the key lock has an open entrance passage I2 in one side thereof which is wide enough to pass the door knob shank. Preferably the ends of the entrance passage are spaced from the ends of the elongated opening. The edges of the entrance passage also may be inclined with respect to the entrance opening thereby further preventing inadvertent removal of the key lock from the door knob shank. The body of the key lock car ries a key retaining member I3 in the form of an extension, stem or strip extending from the body III. This key retaining member engages the eye or loop of the key so as to prevent its turning when it is engaged thereby. The key retaining strip or member is illustrated as engaging in the loop or eye of a key K. When the stem I3 is so engaged in the eye of a key the lattercannot be turned by manipulation of a tool through'the key hole from the outside and thereby prevents removal of the key from the key hole by a person seeking unauthorized entrance.

The stem or strip I3 is off-set a substantial dis tance from the axis of the body or the axis of the elongated opening. In the construction particularly illustrated the edge of the key engaging member corresponds or is in alignment With theedge of the body III which contains the open passage. The axis of the strip also is preferably parallel with the axis of the body. This offset of the key retaining member unbalances the key lock so that the shank S of the door knob rides upon the closed side of the body ID whenthe stem is inserted and removed from the eye of the key. The simplest and customary way to remove the strip from the key eye is to engage the bottom of the device with the finger and push upwardly. Because of the unbalanced construction the shank S of the door knob rides along the closed side of the elongated opening I I and consequently there is no tendency for the door knob shank to be inadvertently projected through the entrance passage I2. Similarly in placing the stem within the eye of a key the finger engages the bottom of the stem and pushes upwardly thereon and because of the unbalanced relation the door knob shank again rides on the closed side of the elongated opening, until the end of the key engaging member is above the key loop whereupon the stem is projected thereinto.

The unbalanced or unsymmetrical construction of the key lock also results in a leverage which further insures that the key lock rides or contacts the door knob shank upon the closed side thereof. This leverage is created by the right hand side of the key loop K serving as a fulcrum when upward pressure is applied to the bottom of the stem I3 which leverage swings or tends to pivot the key lock in a counter-clockwise direction and hence keeps the closed Side of the elongated loop against the door knob shank.

The strip or stem I3 may have central grooves I4 on each side thereof, such as when made of plastic material, in order to accommodate for the points frequently found in the center of the eye of 'the key.

The key lock described herein has and needs no resilient parts and consequently it can be made out of plastic or similar material. It also may be made out of metal if desired but from the standpoint of economy in manufacturing a plastic material which can be molded is more desirable.

This invention is presented to fill a need for improvements in a key lock. It is understood that various modifications in structure, as well as changes in mode of operation, assembly, and manner of use, may and often do occur to those skilled in the art, especially after benefiting from the teachings of an invention. Hence, it will be understood that this disclosure is illustrative of preferred means of embodying the invention in useful form by explaining the construction, operation and advantages thereof.

What is claimed is:

1. A key lock comprising a body having an elongated opening to receive a door knob shank, an entrance passage into the elongated opening on one side of the body and the other side being closed, a key retaining member extending from the body and adapted to engage a key and prevent its turning, and the key retaining member being offset a substantial distance from the axis of the elongated opening in the body whereby the door knob shank rides on the closed side of the elongated opening during insertion and removal of the key retaining member from engagement with a key.

2. A key lock comprising a body having an elongated opening to receive a door knob shank, an entrance passage into the elongated opening on one side of the body and the other side being closed, a key retaining member extending from the body and adapted to engage a key and prevent its turning, and a key retaining member being parallel with and off-set a substantial distance from the central axis of the elongated opening in the body in a direction toward the side having the entrance passage whereby the door knob shank rides on the closed side of the elongated opening during insertion and removal of the key retaining member from engagement with a key.

3. A key lock comprising a body having an elongated opening to receive a door knob shank, an open entrance passage into the elongated opening on one side of the body and the other side being closed, a key retaining member extending from the body and adapted to engage a key and prevent its turning, and the key retaining member being off-set a substantial distance from the axis of the elongated opening in the body with its edge corresponding with the edge of the body whereby the door knob shank rides on the closed side of the elongated openingduring insertion and removal of the key retaining member from engagement with a key.

4. A key lock comprising a body having an elongated opening to receive a door knob shank and permit vertical movement thereupon, an open entrance passage into the elongated opening on one side of the body and the other side being closed, the ends of the entrance passage being spaced from the ends of the elongated opening, a key retaining member extending from the body and adapted to engage the loop of a key and prevent its turning, and the key retaining member being off-set a substantial distance from the axis of the elongated opening in the body with its edge corresponding with the edge of the body, whereby the door knob shank rides on the closed side of the elongated opening during the vertical insertion and removal of the key retaining member from engagement within the loop of the key.

JOHN W. WILEY. 

